www.uptodate.com
Has a very good patients section with downloadable information sheets on many topics

www.mayoclinic.org
World renowned American medical institution has a comprehensive website for patient information

www.gesa.org.au
Website of the Gastroenterology Society of Australia

www.crohnsandcolitis.com.au
Australian inflammatory bowel disease website

www.coeliac.org.au
For coeliac disease information

www.shepherdworks.com.au
For dietary advice relayed to irritable bowel syndrome

www.med.monash.edu/cecs/gastro/fodmap
For dietary advice relayed to irritable bowel syndrome

www.allergy.org.au
A mainstream view of food allergy related gut issues